1. Field of the Invention
This invention relates to bisbiguanide derivatives, and, more particularly to bis-(pyrrolidonyl alkylene) biguanide derivatives having antimicrobial activity.
2. Description of the Prior Art
Bisbiguanides are well known as antimicrobial agents. See, for example, U.S. Pat. Nos. 3,468,898; 4,022,834; 4,567,174; and 4,670,592. The bisbiguanide known as chlorhexidine, or, chemically, 1,6-bis(4-chlorophenylbiguanido)-hexane, is a widely used antimicrobial compound; its formula is: EQU A--Z--A
where A is: ##STR2## and Z is --CH.sub.2 --.sub.6.
However, chlorhexidine is known to have many deficiencies, including: (1) the presence of a mutagenic p-chloroaniline moiety*; (2) low water solubility for the free base; (3) inactivity against bacterial spores at room temperature; (4) an antibacterial activity which is pH dependent in the range of pH 5-8, and which deteriorates at a pH below 5; and (5) incompatability in formulations containing surface active agents. FNT * (1) Scott, A. L. and Eccleston, E. "Investigation of the General Toxic and Heamatological Effects of para-chloroaniline in Several Species" Proc. Env. Soc. Study of Drug Toxicity Neutrotoxicity of Drugs 8, 195-204 (1966); and
(2) Prasad, I, "Mutagenic Effects of the Herbicide 3',4'-Dichloropropionanilide and its Degradation Products", Can. J. Microbiol 16, 369-372 (1970).
Accordingly, it is an object of this invention to provide new and improved antimicrobial bis-biguanide derivatives.
A particular object of the invention is to provide novel antimicrobial biguanides having enhanced water solubility properties, low toxicity and better compatability with surfactants.
These and other objects and features of the present invention will be made apparent from the following particular description thereof.